A Magnetic Random Access Memory (MRAM), which is one type of non-volatile memory, is getting a lot of attention as a semiconductor memory device. For example, the MRAM is manufactured by performing a heat treatment (magnetic annealing treatment) on a magnetic substance film formed on a semiconductor wafer (hereinafter, referred to as a “wafer”) by a magnetic field within a process container kept at a high vacuum such that a magnetic property of the magnetic substance film is developed.
In recent years, in a semiconductor manufacturing apparatus, as an element is becoming denser, a more dense treatment is requested. For that reason, it has become important to reduce the adhesion of particles onto a surface of a wafer. However, if a magnetic annealing treatment is performed within a process container kept at a high vacuum, there is a case in which the adhesion of particles onto the surface of the wafer cannot be sufficiently reduced.